5<>8 A TEXTBOOK OF PHYSIOLOGY 



not appreciate certain smells e.g., mignonette. Such " anosmia '' 

 is probably congenital, but temporary anosmia may occur in disease 

 of the nose and in nervous conditions. It may be induced by the 

 application of drugs, such as cocaine. Parosmia (perverted sense of 

 smell) and hyperosmia (increased sensibility to smells) may also occur 

 in nervous conditions (hysteria, etc.). 



Taste and smell, as we have seen, are intimately related. It is 

 possible for them to be antagonistic. This fact is made use of by the 

 physician. Thus, " tinct. aurantii," by its odour, counteracts the 

 bitter taste of quinine, and effervescing saline drinks (taste) mask, 

 the flavour (odour) of castor oil. 



The central connections for smell are made by means of the olfac- 

 tory lobes of the brain (see p. 715). 





